Two-axle boxcar with full-side closure

ABSTRACT

Cooperating upper and lower closure sections for each side of a two-axle boxcar extend over the full length of the boxcar. A hoisting line, screw, chain or fluid-pressure jack raises the lower closure section into overlapping relationship with the upper closure section and then raises both closure sections conjointly above the side opening. The lower section is guided by cam tracks to move outward as it moves upward and the upper edge of the upper closure section is guided by swinging arms as the sections move about the boxcar body. Alternatively, the lower closure section can swing downward and the upper closure section can be raised edgewise upward to clear the side opening. Retractable props can provide support for the boxcar roof at locations between its ends.

[451 res. 19, rem

Unite States Patent [191 Paton 1,396,420 ll/l92l Glinchikoff.........................105/378 TWO-AXLE BOXCAR WITH FULL-SIDE CLOSURE Inventor:

Primary Examiner-Gerald Ml. Forlenza Hamilton Neil King Paton 2521 W. Montlake Pl. Seattle wash- Asszstant Examiner Richard A. Bertsch 98112 Attorney, Agent, or Firm-Robert W. Beach [57] ABSTRACT Cooperating upper and lower closure sections for each side of a two [22] Filed: Aug. 24, 11972 [21] Appl. No.: 283,356

-axle boxcar extend over the full length of R at d U Appli i n a a the boxcar. A hoisting line, screw, chain or fluid- {62] Division of Ser. No. 821,384, May 2, 1969, Pat. No.

pressure jack raises the lower closure section into 3,687,186. overlapping relationship with the upper closure section and then raises both closure: sections conjointly above the side opening. The lower section is guided by 105/378 cam tracks to move outward as it moves upward and the upper edge of the upper closure section is guided by swinging arms as the sections move about the boxcar body. Alternatively, the lower closure section can swing downward and the upper closure section can be raised edgewise upward to clear the side opening. Re-

[56] References Cited UNITED STATES PATENTS tractable props can provide support for the boxcar roof at locations between its ends.

3,191,547 6/1965 105/378 7 Ciaims, M Drawing Tiger-es PMENTED FEB 1 91974 SHEEI 2 0F 5 TWO-AXILE BOXCAR WITH FULL-SIDE CLOSURE This application is a division of U.S. Pat. application Ser. No. 821,384, filed May 2, 1969, for Boxcar Full- Side Closure issued as US. Pat. No. 3,687,186.

Customarily access to the interior of boxcars has been afforded through a comparatively narrow doorway in the central portion of each side. Consequently, in many instances loading has been difficult and timeconsuming. One reason for providing such access to the interior of boxcars has been the wide variety of lading for which boxcars have been used. It has been considered necessary to provide boxcar structure sufficiently strong to carry the heaviest type of lading, such as machinery, for example, even though for most lading such heavy construction was not necessary.

Proposals have been made for boxcars having side structures which could be opened fully or almost fully, but such structures have been expensive and have had various disadvantages.

It is a principal object of the present invention to provide a boxcar side structure which, while closable, can be opened over substantially the full length of the car and the sides of which car can be closed securely.

More specifically it is an object to provide a full-side closure for a boxcar of rigid character to deter pilferage but which can be opened quickly and easily and which will be economical to construct.

Another object is to provide a full-side closure for a boxcar which, when moved to full-open position, will be in a location which will not interfere with a carloading or car-unloading operation and which will not project from the car in a manner to interfere with building structures alongside the car.

More particularly it is an object to provide a full-side closure for a boxcar which is formed of components that can be disposed in overlapping or nesting relationship when in open position so as to form a compact structure, and which closure may be made of components each of which extends over the full length of the car.

A further object is to provide support members for a full-side opening ofa boxcar which will provide support for the car roof between the ends of the car.

It is also an object to provide a full-side closure for a lightweight boxcar which is supported solely by two axles.

FIG. 1 is a side elevation ofa boxcar according to the present invention with the side closure in closed position and FIG. 2 is a corresponding view with the closure in open position.

FIG. 3 is a top perspective of one end portion of the boxcar with the closure closed;

FIG. 4 is a corresponding view with the closure partially open and FIG. 5 is a similar view with the closure fully open.

FIG. 6 is an end elevation of the boxcar with parts broken away and FIG. 7 is a detail vertical transverse section of a side portion of the boxcar on an enlarged scale.

FIGS. 8, 9 and 10 are similar fragmentary top perspectives of a corner portion of a boxcar showing somewhat modified different forms of the invention.

FIG. 11 is an end elevation of a boxcar having an alternative form of the invention.

FIG. 12 is a fragmentary side elevation of a boxcar showing an auxiliary feature of the invention, parts being broken away;

FIG 13 is a similar view with parts in different positions and FIG. M is a transverse vertical section through the boxcar taken on line ll4-ll4i of FIG. 112.

The principal consideration in the vehicle of the present invention, such as a boxcar, is to provide full access to the interior of the vehicle body so that it can be loaded and unloaded very quickly, while forming a closed rigid structure during transit. Consequently, the closures for the sides are not formed of flexible material, such as fabric, nor even of roll'up construction. On the contrary, each closure section is of rigid construction. Nevertheless, the car structure is of light weight as compared to that of a conventional boxcar. A car according to the present invention is intended for hauling bulky products of relatively light weight, such as dry packaged food products or crated furniture, for example.

Because the boxcar I is not intended to be used to carry heavy lading, its chassis 2 can be of relatively light construction and the car can be carried by a pair of wheels 3 on a single axle at each end of the car. Such a car may be of conventional length, such as approximately 40 feet, and has couplings 4 of conventional type to be connected to other cars in a train. As shown best in FIG. 2, an entire side of the boxcar can be opened, and preferably both sides of the car can thus be opened so that the car can be loaded and/or un- V loaded from either side.

The preferred type of rigid closure provided to close the open sides of the boxcar is shown best in FIGS. 1 to 7, inclusive, as composed of an upper closure section 5 and a cooperating lower closure section 6. These closure sections extend the full length of the opening and are of substantially the same width so that the upper closure section can cover the upper half of the opening and the lower closure section can cover the lower half of the opening. The upper closure section is constructed of a frame providing openings which are covered by panels 7. Upright stiffeners 3 may define the edges of such openings or may simply overlap a longitudinally continuous panel of thin sheet material to stiffen it. correspondingly, panels 9 in the lower closure section 6 can be separated or stiffened by uprights 110.

The lower closure section 6 is suspended from the upper closure section 5 or its supporting structure by several lines It, preferably made of cable. The upper end of these lines are attached to the upper edge portion of the upper closure section by anchoring lugs 12. The lower ends of such lines are attached to the upper edge portion of the lower closure section by lugs 13. The length of each line II. can be: adjusted by turning turnbuckle M to equalize the lengths of all of the suspension lines. The lengths of such lines will be adjusted so that when the closure sections are in the closed position shown in FIGS. 1 and 3 and at the right of FIG. 6, the lower edge of the lower closure section 6 will be disposed alongside the sill of the chassis 2. The lower edge of the lower closure section can then be latched to the sill by bolts of latches I5 engaging in the respective latch bolt sockets 16.

In order to open the closure shown in FIGS. 1 to 9, inclusive, the lower closure section 6 is first shifted bodily outward into a position offset from the upper closure section 5 and is then slid edgewise upward into the overlapping relationship with the upper closure section as shown in FIG. 4. Both closure sections are next slid edgewise upward conjointly to a location above the upper edge of the car side opening and projecting above the car body as shown in full lines in FIG. 5 and in broken lines in FIG. 6. Various types of closurehoisting means can be utilized to accomplish such movement. A hoisting line and winch arrangement for this purpose is shown in FIGS. 1 to 5, inclusive.

As shown best in FIGS. 3, 4 and 5, one end of the closure-hoisting line 17 is attached to the line-attaching projection 18 which projects from the lower edge portion of an end of the lower closure section 6. From such projection the line extends upward over an idler guide pulley 19 mounted on the upper portion of an upper thrust plate 20 attached rigidly to the car side. Such thrust plate overlaps the upper closure section 5 and is located in close proximity to the end of such closure section so that any lengthwise movement of the upper closure section would cause its end to engage the plate 20 to limit such lengthwise movement.

From the idler-hoisting line guide pulley 19 the hoisting line 17 extends downward to a lower hoisting line guide pulley 21 and around it to a hoisting line drum 22. Such drum is driven by an endless chain 23 extending around a sprocket 24 mounted on the drum shaft and a sprocket 25 mounted on an actuator drive spindle 26. Such spindle could be rotated by a hand crank, but preferably is rotated by applying to it a power drive such as the chuck of an electric drill. The drum may include a brake 22' which will permit the drum to turn only in the line-winding direction unless such brake is positively disengaged.

Lower thrust plates 27 are mounted on the boxcar frame adjacent to opposite ends, respectively, of the lower closure section 6. Appreciable lengthwise movement of such section would cause one end or the other of it to engage a lower thrust plate to limit such endwise movement. Such thrust plates serve the further function of providing cam actuation for the lower closure section to wedge it outwardly as it is raised so that it will be hoisted outward from the upper closure section 5. For this purpose, the lower end portion of the thrust plate 27 has a downwardly and inwardly inclined edge portion 27 with which a rod 18 projecting lengthwise of the car from the lower edge portion of the lower closure section 6 engages. As such closure section is hoisted, the rod riding on such inclined edge will wedge the lower portion of the section outward.

In order for the lower closure section 6 to slide upward alongside the upper closure section 5 it is necessary for its upper edge portion as well as its lower edge portion to be shifted outwardly into a position offset from the upper closure section. To accomplish this pur' pose a cam-follower roller 28 is mounted on the end edge of the upper portion of the lower closure section as shown in FIG. 7, which roller is engaged between the flanges of the channel cam track 29, shown best in FIGS. 3 and 7, mounted on an end portion of the upper closure section 5. The lower portion of such cam track is inclined inwardly and downwardly generally corresponding to the slope of the cam edge 27 on the lower portion of the thrust plate 27.

When the closure sections 5 and 6 are in their lower positions closing the side opening, sealing strips 30 around their edges will bear against the opening edges to seal the opening. Also the seal strip 3H carried by flange M on the upper edge of the lower closure 6 will bear against the lower portion of upper closure 5 to provide a seal of the joint between the closures. As the actuator drive spindle 26 is rotated to turn the drum 22 in the line-winding direction, the lower closure section 5 will be raised from the position shown in FIG. 3 to that of FIG. 4. During such movement the camfollower roller 28 will move upward and outward along the inclined portion 29' of the channel cam track 29 and at the same time the projecting rod I8 on the lower portion of the lower closure section will ride upward and outward along the correspondingly inclined cam edge 27' of the thrust plate 27. The slopes of these cam members will be sufficient to displace the lower closure section 6 outward a distance equal to the thickness of the upper closure section so that the lower closure section will move into overlapping registry with the upper closure section and alongside it as shown in FIG. 4.

As the lower closure section 6 is hoisted toward regis try with the upper closure section 5 in the position shown in FIG. 4, the weight ofthe lower closure section will be assumed by the hoisting lines 17 and I7 at its opposite ends and the lines ill which previously suspended the lower closure section will be relieved of load. Such suspension lines will simply be draped in loops as shown in FIG. 4. When the lower closure section is hoisted into full registry with the upper closure section as shown in FIG. 4, the upper edge of the lower closure section will engage the hoisting thrust plates 32 secured to the upper edge of the upper closure section. The hoisting force applied through line I7 to the lower closure section 6 will then be transferred through the thrust plates 32 to the upper closure section 5.

Swinging guide arms 33 having their lengths extending transversely of the car have corresponding ends anchored by hinges 34 to the boxcar roof 35. The swinging end of each arm is hinged to the upper portion of the upper closure section 5 by a hinge 36. As the hoisting force is transmitted to the upper closure section, the lower closure section and the upper closure section will be hoisted conjointly in overlapping registry from the position shown in FIG. 4 to that of FIG. 5. The guide arms 33 will prevent uncontrolled movement of the upper portion of the upper closure section as it is raised. The upper portions of the overlapping closure sections actually will move along an are having a radius equal to the length of a guide arm 33 so that the upper portions of such closure sections will be displaced to some extent toward the central portion of the car as shown most clearly in broken lines in FIG. 6. As the arms approach their upper positions of FIG. 5 the bracing guy lines 33 sloping oppositely from the end arms will tighten to prevent lengthwise movement of the closure sections.

After a loading or unloading operation through the fully-open side of the boxcar has been performed, the closure sections can be lowered to cover the side opening by rotating the actuator drive spindle 26 in the opposite direction. By such operation the two closure sections will descend in overlapping registry from the position shown in FIG. 5 and in broken lines in FIG. 6 to that of FIG. 4.. Conjoint downward movement of the sections will be interrupted by engagement of the swinging guide arms 33 with the roof 35 of the boxcar.

Continued rotation of the actuator drive spindle in the same direction will result in the lower closure section 6 moving downward relative to the upper closure section 5 from the position shown in FIG. 4 to that of FIG. 3.

In order to reduce the load which would be required to be applied to the actuator drive spindle 216 for hoisting the closure sections 5 and 6, a counterweight 17'', shown in FIGS. 3, 4 and 5, equal to somewhat less than half the weight of the lower closure section 6 can be attached to the stretch of line 17 between the upper guide pulley l9 and the lower guide pulley 21. Also, when the closure sections have reached their fullyraised positions shown in FIG. 5, a spring-pressed latch bolt l5 can engage beneath the projection 13 on the lower portion of the lower closure section 6 as shown in FIG. 5 to hold the closure sections positively in their uppermost open positions even though hoisting force is no longer applied to the actuator drive spindle 2s. A bell crank connected to the latch bolt can be swung by engaging a hook in the eye of its horizontal arm to retract the latch bolt thus releasing the closures for downward movement.

To raise the closure sections in horizontal positions so that they will not bind by engagement with the end thrust plate 20 and 27, it is necessary that the hoisting of the opposite end portions of such closure sections be precisely coordinated. For this purpose the hoisting lines 17 and 17', attached to the opposite ends of the lower closure section, respectively, will both be wound on the same hoisting line drum 22 at one end of the boxcar. The line 17' connected to the end of the lower closure section 6 at the end of the boxcar opposite the drum 22 can be passed around the idler guide pulley 21' to be fed onto such drum.

When the hoisting force is applied to the projections 18 at the lower edge of the lower closure section 6 there may be a tendency for the upper edge portion of the lower closure section and the lower edge portion of the upper closure section to buckle outward from the car. Also, simply the weight of the upper closure section 5 may not be sufficient to press sealing strips 30 of the upper closure section tightly against the car wall around the edges of the closure section to seal the junc tion between them. To insure that the lower portion of the upper closure section 5 will be held tightly against the car frame, both when the closure is closed and during the initial portion of the closure opening operation, a further latch in the form of a spring-pressed plunger can be mounted on the lower portion of the thrust plate 21), as shown in FIGS. 3, 4- and 5, to engage with the lower portion of the upper closure section 5. Engagement of the cam-follower roller 28 in the inclined portion 29' of the channel cam track 29 will in turn hold in the upper portion of the lower closure sec tion 6 to press its sealing strip 31 firmly against the lower portion of upper closure 5.

Instead of utilizing the hoisting line to hoist the upper and lower closure sections as shown in FIGS. 1 to 7, a screw actuator of the type shown in FIG. 8 can be used. In this instance the screw 37 is disposed with its length upright and its upper end mounted in a bearing on the car frame. A traveling nut 3F is moved up and down along the screw by'rotation of the screw effected by rotation of the actuator drive sprindle 40 turning suitable angle gearing 411. An arm 42 projects transversely of the screw from the traveling nut and has in it a slot 43 extending lengthwise of the arm in which the projection I8 projecting from the lower portion of the lower closure section tit is engaged. As the screw 37 is rotated in one direction or the other, the projection 18 will be raised or lowered correspondingly to hoist or lower the closure sections 5' and 6 in the manner described in connection with FIGS. 1 to 7.

FIG. 9 shows a different arrangement for hoisting the lower closure section 6. In this instance a short line 44, preferably of cable, connects the closure section projection lift to a suitable fitting on an endless chain 44'. The stretches of this chain are upright and it extends around an upper idler sprocket t5 rotatively mounted in a bearing mount llti and around a lower drive sprocket d7. Such drive sprocket is carried by suitable drive gearing Altl which is turned by rotation of the actuator drive spindle 49. Rotation of the drive spindle will move up or down the stretch of the chain to which the line 4 3 is attached for again hoisting or lowering the closure sections 5 and 6 in the manner described in connection with FIGS. 1 to 7'.

In order to eliminate the necessity of applying a continuous force to the drive spindle 49 and to hold the closure sections in any elevated position which may be desired, a ratchet pawl S ll can be provided to cooperate with a gear mounted on the same shaft as the lower drive sprocket 4-7, which pawl can be released manually when it is desired to lower the closure sections. Also holding means in the form of a unidirectional friction or fluid brake 15' can be connected to the shaft of sprocket 35 to retard rotation in the closuredescending direction for limiting the speed of descent of the closure sections.

The closure section construction of FIG. ll llt is similar to that described above except that still a different type of mechanism is provided to exert the lifting force on the projection 18 at the bottom of the lower closure section ti. In this instance the lifting mechanism includes a multiple-cylinder telescopingjack 37, the sections of which in the closed positions of the upper closure section 5 and lower closure section 6 are retracted into a well 37" depending from the chassis 2. Such telescoping jacks at opposite ends of the opening can be extended by supplying fluid under pressure to them which may either be air under pressure from a suitable source or may be hydraulic liquid supplied by a pump from a reservoir slung beneath the car. Such pump can be driven by an electric motor supplied with current from the track side.

While in the illustration of FIGS. 1 to lit), inclusive, the lower closure section 6 has been shown and described as being moved upward from its closed position, FIG. III shows an alternate arrangement in which the lower closure section 51 is swung from its closed position downward into open position about a hinge S2 mounting its lower edge. In this instance the upper edge of the lower closure section has a standing bevel and the lower edge of the upper closure section 5 has a complemental under bevel which overlaps the standing bevel of the lower closure section. Because of the cooperation of these beveled edges, it is necessary for the upper closure section to be raised before the lower closure section can be swung downward. Downward swinging of the lower closure section is controlled by paying out lines 53 connected between the swinging edge portion of the lower closure section and suitable winding drum mechanism not shown. Winding in the lines 53 will swing the lower closure section from downwardly-swung open position into upright closed position.

FIGS. 12 to 14, inclusive, disclose a prop device which may be provided as an accessory to afford additional support for the long span of the boxcar roof 35 if desired. One or more props are arranged at suitable locations lengthwise of the boxcar. Each prop is shown as including a column 59 swingably supported by a pivot 60 from the boxcar chassis 2. Such pivot is mounted in one end portion of a recess 61 provided in the chassis which is of a length great enough to receive the prop when the jack 62 is in the contracted position of FIG. 13. Fluid under pressure can be supplied to such jack through connection 63. The supporting force of the prop is distributed over an appreciable area of the boxcar roof 35 by the prop plate 64.

The boxcars shown in FIGS. 1 to 14 are supported solely by two axles, each one near each end of the boxcar, each axle having a pair of wheels 3.

Particularly for light lading, it may be desirable to provide means for exerting pressure between such lading and the upper and lower closure sections to deter shifting of the lading. Such pressure can be effected by an inflatable liner 65 shown in FIG. 7. Such liner can be made as a single unit or in sections, and can be removable for access to the interior of the boxcar when the closure is open or can simply be rolled up to the roof of the car in deflated condition. Alternatively, the inner sides of the closure sections could be hollow and the liner could be received in such hollows in deflated condition. When the closures have been moved into the closed position shown in full lines in FIG. 7, the liner can be inflated to fill the space between the closure means and the lading. Such liner would, of course, be deflated before initiating a closure-opening operation.

I claim:

1. A vehicle for transporting light, bulky articles comprising an elongated body, a single axle located at one side of the transverse center line of said body and constituting the sole supporting means for said body between such center line and one end of said body, wheels supporting the opposite ends of said axle, additional supporting means including wheel means located at the other side of the transverse center line of said body, said body including a roof and having a side opening extending substantially from end to end of said body and from its floor upward at least almost to said roof to facilitate loading of light, bulky articles into said body transversely of its length, a rigid closure for closing at least the upper portion of said opening, and means connected between the upper portion of said closure and a portion of said roof spaced from the vehicle side a substantial distance toward the center of the vehicle and operable to guide said closure for movement edgewise upward exteriorly of said body substantially completely out of registration with said opening to dispose a substantial portion of said closure above said roof.

2. The vehicle defined in claim 1, in which the additional supporting means includes a second single axle located at such other-side of the transverse center line of the body and constitutes the sole supporting means for the body between such transverse center line and the other end of the body, and the Wheel means includes wheels supporting the opposite ends of said second axle.

3. A vehicle for transporting light, bulky articles comprising an elongated body, a single axle located at one side of the transverse center line of said body and constituting the sole supporting means for said body between such center line and one end of said body, wheels supporting the opposite ends of said axle, additional supporting means including wheel means located at the other side of the transverse center line of said body, said body including a roof and having a side opening extending substantially from end to end of said body and from its floor upward at least almost to said roof to facilitate loading of light, bulky articles into said body transversely of its length, a rigid closure including an upper rigid closure section for closing the upper portion of said opening and a lower rigid closure section for closing the lower portion of said opening, means operable to guide said upper closure section for movement edgewise upward exteriorly of said body substantially completely out of registration with said opening to dispose a substantial portion of said upper closure section above said roof, and means guiding said lower closure section for movement upward into overlapping relationship with said upper closure section when said upper closure section is in its upper position to dispose a substantial portion of said lower closure section above said roof.

4. The vehicle defined in claim 3, in which the additional supporting means includes a second single axle located at such other side of the transverse center line of the body and constitutes the sole supporting means for the body between such transverse center line and the other end of the body, and the wheel means includes wheels supporting the opposite ends of said second axle.

5. A vehicle for transporting light, bulky articles comprising an elongated body including a roof and a lading-supporting structure having a floor, said body having a side opening extending substantially from end to end of said body and from said floor upward at least almost to said roof to facilitate loading of light,

bulky articles into said body transversely of its length,

tion of said opening, means operableto guide said closure means for movement edgewise substantially completely out of registration with said opening, and an extendible prop located between the ends of said body, extendible elevationally to span between the top and bottom of said body side opening and retractable out of registration with said body side openmg.

6. The vehicle defined in claim 5, in which the prop includes a telescoping jack retractable into a well below the body side opening.

7. The vehicle defined in claim 5, in which the prop includes a column and a jack supported by said column, the body includes a prop-receiving recess below the body side opening, and pivot means in said recess mounting the lower end of the prop for swinging from upright attitude downwardly into said recess. 

1. A vehicle for transporting light, bulky articles comprising an elongated body, a single axle located at one side of the transverse center line of said body and constituting the sole supporting means for said body between such center line and one end of said body, wheels supporting the opposite ends of said axle, additional supporting means including wheel means located at the other side of the transverse center line of said body, said body including a roof and having a side opening extending substantially from end to end of said body and from its floor upward at least almost to said roof to facilitate loading of light, bulky articles into said body transversely of its length, a rigid closure for closing at least the upper portion of said opening, and means connected between the upper portion of said closure and a portion of said roof spaced from the vehicle side a substantial distance toward the center of the vehicle and operable to guide said closure for movement edgewise upward exteriorly of said body substantially completely out of registration with said opening to dispose a substantial portion of said closure above said roof.
 2. The vehicle defined in claim 1, in which the additional supporting means includes a second single axle located at such other side of the transverse center line of the body and constitutes the sole supporting means for the body between such transverse center line and the other end of the body, and the wheel means includes wheels supporting the opposite ends of said second axle.
 3. A vehicle for transporting light, bulky articles comprising an elongated body, a single axle located at one side of the transverse center line of said body and constituting the sole supporting means for said body between such center line and one end of said body, wheels supporting the opposite ends of said axle, additional supporting means including wheel means located at the other side of the transverse center line of said body, said body including a roof and having a side opening extending substantially from end to end of said body and from its floor upward at least almost to said roof to facilitate loading of light, bulky articles into said body transversely of its length, a rigid closure including an upper rigid closure section for closing the upper portion of said opening and a lower rigid closure section for closing the lower portion of said opening, means operable to guide said upper closure section for movement edgewise upward exteriorly of said body substantially completely out of registration with said opening to dispose a substantial portion of said upper closure section above said roof, and means guiding said lower closure section for movement upward into overlapping relationship with said upper closure section when said upper closure section is in its upper position to dispose a substantial portion of said lower closure section above said roof.
 4. The vehicle defined in claim 3, in which the additional supporting means includes a second single axle located at such other side of the transverse center line of the body and constitutes the sole supporting means for the body between such transverse center line and the other end of the body, and the wheel means includes wheels supporting the opposite ends of said second axle.
 5. A vehicle for transporting light, bulky articles comprising an elongated body including a roof a lading-supporting structure having a floor, said body having a side opening extending substantially from end to end of said body and from said floor upward at least almost to said roof to facilitate loading of light, bulky articles into said body transversely of its length, rigid closure means for closing at least the upper portion of said opening, means operable to guide said closure means for movement edgewise substantially completely out of registration with said opening, and an extendible prop located between the Ends of said body, extendible elevationally to span between the top and bottom of said body side opening and retractable out of registration with said body side opening.
 6. The vehicle defined in claim 5, in which the prop includes a telescoping jack retractable into a well below the body side opening.
 7. The vehicle defined in claim 5, in which the prop includes a column and a jack supported by said column, the body includes a prop-receiving recess below the body side opening, and pivot means in said recess mounting the lower end of the prop for swinging from upright attitude downwardly into said recess. 